U.S. patent number 7,393,285 [Application Number 10/762,344] was granted by the patent office on 2008-07-01 for putter with alignment means.
Invention is credited to Bernt Stellander.
United States Patent |
7,393,285 |
Stellander |
July 1, 2008 |
Putter with alignment means
Abstract
A putter head having a forward-facing striking surface, a heel,
a toe, a top surface and a rearward-facing, elongated tail section.
The elongated tail section has vertical side walls, into each of
which is machined an elliptical track or groove along the inside
surface. The elliptical tracks are spaced from each other at a
width slightly less than the diameter of a golf ball, and are
machined into the sidewalls at a predetermined angle of incidence
such that, when viewed from directly overhead, the tracks will be
perceived by the user as two parallel lines. If the user's eyes are
not directly in line with the plane extending vertically from the
centerline, then one of the tracks will increasingly disappear
behind its respective sidewall, while the opposite track will
appear to become increasingly curved, as the degree of misalignment
increases. The putter thus provides a means of alignment that
improves putting accuracy.
Inventors: |
Stellander; Bernt (Skollenborg,
NO) |
Family
ID: |
38649007 |
Appl.
No.: |
10/762,344 |
Filed: |
January 23, 2004 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20070254748 A1 |
Nov 1, 2007 |
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Current U.S.
Class: |
473/251; 473/255;
473/254; 473/253; 473/252 |
Current CPC
Class: |
A63B
53/0487 (20130101); A63B 53/0441 (20200801) |
Current International
Class: |
A63B
69/36 (20060101) |
Field of
Search: |
;473/219-256,340-341,313
;D21/736-746 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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54156737 |
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Dec 1979 |
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JP |
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2001 178857 |
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Jul 2001 |
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JP |
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2002 239045 |
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Aug 2002 |
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JP |
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Primary Examiner: Passaniti; Sebastiano
Attorney, Agent or Firm: Abel; Christian D.
Claims
The invention claimed is:
1. A putter head for a golf putter, comprising: A forward-facing,
planar striking surface; a toe section; a heel section; a top
surface; and an elongated, rearward projecting tail section, said
tail section comprising reference tracks that, when viewed from
above by a user whose eyes are in vertical alignment with the
perpendicular centerline bifurcating said striking surface, will
appear to the user as two continuous parallel lines that are
equidistant from the centerline and that extend perpendicularly to
said planar striking surface in the rearward direction, and wherein
said tracks, when viewed from above by a user whose eyes are not in
vertical alignment with the perpendicular centerline, will not
appear as two continuous parallel lines, wherein said tail section
comprises two substantially vertical sidewalls, a floor section, a
rear section and a front wall section that together define a hollow
cavity, and wherein said reference tracks are located along the
inside faces of said sidewalls.
2. The putter head according to claim 1, wherein each reference
track comprises the upper surface of a portion of its respective
sidewall that protrudes in towards the interior of the hollow
space, and further wherein said reference tracks are between 0.5 mm
and 2.0 mm in width.
3. The putter head according to claim 2, wherein said reference
tracks, when viewed from the side, are elliptical in shape, with
the lowest point of arc of the ellipse nearest the floor
section.
4. The putter head according to claim 3, wherein the planes defined
by said elliptical reference tracks have a predetermined angle of
incidence relative to the vertical plane extending up from the
centerline, said angle of incidence being a function of the
distance between the user's eyes and the lowest point of arc of the
tracks.
5. The putter head according to claim 4, wherein the upper surface
of said reference tracks has a color that contrasts with the putter
head.
6. The putter head according to claim 2, wherein each of said
reference tracks is comprised of two straight, substantially
horizontal upper portions and an intermediate, straight and
substantially horizontal lower portion.
7. The putter head according to claims 2 or 6, further comprising a
semicircular indicator marking of contrasting color arranged on the
said top surface of said putter head at the centerline, said
indicator marking having a radius of between 5.1 mm and 5.9 mm and
is offset from center in the forward direction by between 2.1 mm
and 2.9 mm.
Description
FIELD OF THE INVENTION
The present invention relates to golf clubs and, more particularly
to a putter with an alignment means that provides visual feedback
during the setup and the stroke itself.
BACKGROUND OF THE INVENTION
A putter is a golf club used on the short-surface of a golf course,
called the green. The putter is used to strike the ball along the
surface of the green into the hole; a golf shot known as the
"putt".
There are two critical phases in executing a proper putt. In order
to putt accurately, the player needs to (a) achieve a proper stance
and setup and to (b) properly execute the stroke.
The proper stance for putting includes: 1) The player positioning
his/her feet and body parallel to the aiming/putting line. This
imaginary straight line goes from the center of the hole, to the
center of the ball, on a flat, horizontal surface. On undulating
greens, this straight line is aimed to the side of the hole. 2)
Before the stroke is performed, the putter should be positioned
towards the back of the ball, so that the face is square
to/perpendicular to the aiming/putting line. Then the center line
of the putter is in line with the aiming/putter line. The center
line of the putter is an imaginary line, dividing the putter in two
equal halves, from front/face to back. 3) The putter should be
placed behind the ball so that the ball is positioned on the center
of the putter/face. 4) The players eyes should be positioned
parallel to, and perpendicularly above (at an optimal height
depending upon how tall the player is, or his particular putting
style), the center line of the putter when the player is in
position to perform the stroke (set up position).
Once the proper stance is achieved, the stroke must be executed.
The correct/optimal stroke when using a pendulum-type putter is a
"straight back-straight through" movement of the club head. During
the stroke the player's head should not move.
Because of the exacting nature of putting, several efforts have
been made to design a putter with an alignment system to help
improve putting accuracy. Examples of such putters include U.S.
Pat. Nos. 5,720,668; 6,200,227; 6,261,190; and 6,663,496. These
patents are representative of alignment systems that assist the
player in achieving a proper stance, and include visual means that
aid the player in confirming that his/her head is directly above
the putter during set up. While these putters and other known
putters may be somewhat effective in aiding the player to position
himself directly above the ball, none of these putters provide
adequate visual feedback during the stroke itself. Nor do they take
into consideration the effect of one's dominant eye on the visual
feedback. There exists therefore a need for a putter that aids the
player in both of these critical phases.
BRIEF SUMMARY OF THE INVENTION
The present invention is a putter that provides reference markings
for achieving a proper stance, as well as providing visual feedback
through the user's peripheral vision during the stroke itself. The
reference markings of the putter aid the user in positioning
his/her head directly over the ball, at the proper height, and aid
in centering the ball on the striking surface of the putter. The
markings further aid the player in keeping the centerline of the
putter parallel with the aiming/putting line throughout the
stroke.
The putter according to the invention comprises a putter head
having a forward-facing striking surface, a heel, a toe, a top
surface and a rearward-facing, elongated tail section. The
elongated tail section has vertical side walls, into each of which
is machined an elliptical, preferably semicircular, track or groove
along the inside surface. The elliptical tracks are spaced from
each other at a width slightly less than the diameter of a golf
ball, and are machined into the sidewalls at a predetermined angle
of incidence such that, when viewed from directly overhead, the
tracks will be perceived by the user as two parallel lines, such
lines being parallel with and equidistant from the center line of
the putter. The top surfaces of the tracks are preferably painted
in a contrasting color so as to emphasize the visual perception of
the parallel lines.
The elliptical tracks provide an improved means of aiding the user
in centering his/her head directly above the ball at setup. If the
user's eyes are not directly in line with the plane extending
vertically from the centerline, then one of the tracks will
increasingly disappear behind its respective sidewall, while the
opposite track will appear to become increasingly curved, as the
degree of misalignment increases.
The angle of incidence at which the tracks are machined into the
sidewalls is predetermined based upon the optimal height of the
users' eyes above the lowest point of arc of the elliptical tracks.
If the users' eyes are at a lower height, then the perceived
parallel lines will become distorted. If the users' eyes are higher
than intended, then the parallel lines will increasingly disappear
behind the sidewalls. The putter can thus be custom calibrated for
players of different height, or to the unique putting style of the
individual.
The top surface of the putter head further comprises a
semi-circular marking of predetermined radius and offset that
visually aids the user in centering the ball along the striking
surface.
The elliptical tracks of the putter also provide improved visual
feed back during the stroke itself. When the user properly executes
the putting stroke by moving the putter straight back and straight
through (i.e. parallel to the putting/aiming line), the spacing and
parallel appearance of the tracks imparts a sensation that can be
described as "putting the ball in a tube". If the stoke deviates
from the putting/aiming line, however, the user will receive
immediate visual feedback. The user's peripheral vision will
detect, as during the setup, that one of the tracks disappears
while the other becomes increasingly curved. Because visual
perception is extremely sensitive to deviations from straight lines
and parallel relationships, the user will be able to detect errors
in the putting stroke better than with other known putters.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the putter head.
FIG. 2 is a top view of the putter head.
FIG. 3 is a top view, slightly in perspective, of the putter
head.
FIG. 4 is a sectional view of the putter head taken along A-A of
FIG. 2.
FIG. 5 is a sectional view taken along B-B of FIG. 2.
FIG. 6 is a graphical illustration of the formula for calculating
the angle of incidence of the elliptical tracks, wherein "H" is the
height from the eyes to the lowest point of arc, w/2 is the
distance from the center line to the lowest point of arc, and X is
the angle of incidence.
FIGS. 7a and 7b are exaggerated illustrations of a track machined
into a straight and curved sidewall, respectively
FIG. 8 is a perspective view of an alternate embodiment of the
putter head
FIG. 9 is a top view of the putter head from FIG. 8, showing the
visual effect in the case of misalignment
DETAILED DESCRIPTION OF THE INVENTION
The present invention is a putter head that improves putting
accuracy. The following description is made with reference to a
putter designed for a right-handed player therein a hosel (not
shown) will be provided at the appropriate location by one skilled
in the art; however the invention may also be adapted for the left
handed player by providing for an alternative location of the hosel
by one skilled in the art.
The preferred embodiment shown in FIGS. 1-5 comprises a forward
facing striking surface 10, a toe section 12, a heel section 14
(whereat a hosel will be provided for attachment of a shaft), a top
surface 16 and a rearward-projecting tail section 18. As shown in
FIG. 1, tail section 18 comprises two vertical sidewalls 20, a
floor section 22, a rear section 24 and a front wall section 26,
said front wall section 26 being essentially the opposite face of
striking surface 10. As can be appreciated from FIG. 1, sidewalls
20, floor section 22, rear section 24 and front wall section 26
define a hollow cavity hereinafter referred to as targeting box 28.
In a preferred embodiment, floor section 22 curves upward toward
rear section 24, thus producing a rounded appearance at the rear of
tail section 18 as shown in FIG. 4, providing clearance between the
rear of tail section 18 and the ground during the follow-through of
a putting stroke.
As shown in FIGS. 1-5, an elliptical track 30 is machined into each
of sidewalls 20, for example by using a grinding disc of
appropriate radius. Tracks 30 are machined into sidewalls 20 at a
predetermined angle of incidence "X" relative to the vertical plane
extending upwards from the center line of the putter, such center
line being shown as A-A in FIG. 2. Angle "X" is calculated based
upon the optimal height of a user's eyes above the lowest point of
arc of elliptical tracks 30. This optimal distance can be
individually determined for each player (in the case of a custom
putter), or may be based upon accepted norms in the golfing art for
players of various heights.
The formula for calculating angle "X" is graphically represented in
FIG. 6, wherein "H" is the height from the eyes to the lowest point
of arc, W/2 is the distance from the center line to the lowest
point of arc (half the width of floor section 22), and X is the
angle of incidence. According to the laws of right triangles,
TANGENT X=H/(W/2). In a preferred embodiment, the width of floor
section 22 is slightly less than the diameter of a golf ball, and
more preferably 40 mm. If, for example, the optimal distance for a
particular user from the eyes to the lowest point of arc were 1200
mm, then, for that preferred embodiment, angle "X" would be 89.045
degrees.
When tracks 30 are machined at the correct angle of inclination, a
user that is positioned at the correct height, with his/her eyes in
vertical alignment with center line A-A, will perceive tracks 30 as
two parallel lines, as shown in FIG. 2. (If tracks 30 were not
machined at an angle, then the lowest points of the arcs of the two
tracks would appear closer together than the ends of the arcs, due
to the eyes being relatively closer to the end points. The tracks
would then appear slightly curved.) In order to enhance this visual
perception the top surface of tracks 30 can be painted in a color
that contrasts with the color of the putter head. In a preferred
embodiment, the putter head will have a dark, preferably black
color, and tracks 30 will be painted a light color, preferably
white. Because tracks 30 are perceived as parallel lines, the
tracks provide an optical feedback if user's head is misaligned.
FIG. 3 demonstrates how tracks 30 will be perceived by a user whose
head is misaligned in the direction of heel section 14. As seen,
the uppermost track 30 will be perceived by the user as a curved
line, and the bottom-most track 30' will effectively "disappear"
behind its respective sidewall. This same visual feedback is
provided during the putting stroke, wherein it is desirable to keep
the putter head parallel with the aiming line. It is well known in
the optical arts that the human eye is particularly sensitive to
deviations from straight and parallel lines. The tracks will thus
provide a much more sensitive aid for the user than previously
known devices. The "sensitivity" of the invention can be adjusted
further if desired by for example increasing or decreasing the
relative height difference between the end points of track 30 and
the lowest point of arc (for example by machining tracks 30 with a
grinding disc of different radius). An alternate method of
increasing the "sensitivity" would be to increase the height of
sidewalls 20 at their midpoint, so as to increase the distance from
the tops of the sidewalls to the lowest point of arc.
In order for tracks 30 to be perceived as parallel lines, it is
preferred that the tracks have a uniform width. In a preferred
embodiment the width is 1.5 mm, however this width can be increased
or decreased in order to alter the "sensitivity" of the device.
Because tracks 30 are machined into sidewalls 20 at an angle, the
width of tracks 30 would not be uniform if sidewalls 20 are
perfectly planar. If sidewalls 20 were planar, as depicted in
exaggerated illustration 7a, the track at lowest point of the
ellipse would have the full width but would increasingly become
thinner and thinner towards the end points at the tops of the
sidewalls. To compensate for this phenomenon, sidewalls 20 are
slightly curved, as depicted in exaggerated illustration 7b. This
allows for tracks 30 to be machined into sidewalls 20 at full
thickness throughout their length.
As shown in the figures, the putter head according to the invention
further comprises a semicircular indicator 32 engraved or imprinted
on top surface 16, at the center line. Indicator 32 provides visual
feedback aiding the user to center the striking surface with the
ball (not shown). In a preferred embodiment, indicator 32 is white
in color, and has a radius between 5.1 mm and 5.9 mm, and
preferably 5.5 mm. Indicator 32 is offset in the forward direction
by between 2.1 mm and 2.9 mm, and preferably 2.5 mm. These
particular dimensions and color have been shown to create a
particularly effective optical illusion when striking surface 10 is
positioned adjacent to the ball, whereupon indicator 32 appears to
"melt into" the ball and effectively disappear. If the putter head
is not correctly aligned, a gap will appear.
FIGS. 8 and 9 show an alternate embodiment of the invention wherein
each elliptical track 30 is replaced by two planar, upper tracks 34
and an intermediate, lower planar track 36. The visual feedback
from this embodiment is illustrated in FIG. 9, which shows the how
the tracks are perceived by a user whose head is misaligned in the
direction of heel section 14.
In another alternate embodiment (not shown) a curved strip of
appropriate material could be placed between sidewalls 20, and
resting on tracks 30, so that one solid path/line is visible. The
same visual effect is achieved, but now with one solid, wide band,
preferably in the same color as the ball.
While this invention has been shown and described with respect to
specific embodiments thereof, it will be understood by those
skilled in the art that various changes in form and detail thereof
may be made without departing from the scope of the claims of the
invention.
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